GPS, Underground / indoor GPS repeater maintains your position
By Darren Murph 
posted February 21st 2007 10:32AM
posted February 21st 2007 10:32AM
Sure, there's a number of uber-sensitive GPS receivers out there that claim to maintain your position whilst under a bridge, in a tunnel, or cramped up in some thick-walled office building, but a recent patent application is looking to implement a repeater system to ensure the best possible geo-location data regardless of your surroundings. Rather than utilizing a WiFi / GPS hybrid method to keep track of objects, the GPS repeater system would require multiple GPS antennae to be setup atop buildings and other obstructions, which would be wired to an indoor RF repeater system that directional receivers could tap into. The indoor segment would not only repeat the signals, but it would reportedly amplify them as well to ensure a solid connection. While we've no idea if this admittedly bright idea will ever go commercial, we can't help but wonder how folks like Jack Bauer already seem to be taking advantage of it.
We have some of these at work and they've been around for years. There's a GPS antenna on the roof and an RF repeater inside our large garage area so that the military vehicles can be tested with full GPS support. Operation requires an FCC license though. This earned the company we purchased from an FCC investigation for not checking for licenses.
yeah, this seems so simple, it's like "why wasn't it done before?" Apparently it was, and our good buddy the FCC has something to say about it. USA, USA, USA!
*sigh*
When are we supposed to start innovating again?
Don't question Jack Bauer.
Dude Cisco Aironet AP's can track objects for you via triangulation and they give your building wireless network access. Why you would you spend money on this? You really need GPS in a building? What u gonna do w/ ur lat/lon at your desk? hey boss, its 15 feet from my desk to the copier! Retarded.
I was thinking the same thing. Then this popped in my head.
Firefighters. There are some pretty large buildings out there that a group of firefighters might find themselves in. Because of the smoke they wouldn't be able to see very far. However a layout of the building in a GPS unit and the repeaters working would be the next best thing to a clear line of sight. They would be able to navigate through the building much easier.
Now somebody needs to come up with a package tracking method so you can see the GPS location of your package in that superwarehouse environment. I can almost see the TomTom unit on a forklift now.
The linked patent was filed in 2003. How is this new?
I was looking for a commercial product like this a few years back, for tracking of 600 vehicles in a large garage, to find the vehicle we want to service (oil change, engine overhaul, etc.). I wonder whether anyone has commercialize this or not.
We, AeroScout http://www.aeroscout.com is using the Wi-Fi based RFID to achieve the in-door location tracking. The type of the application that "Bigboss" had mentioned above is one of our mature application in the field. You are more then welcome to contact me for more details.
Hello guys,
I thought I'd add a comment on the technical side. First of all, there's a difference between simple re-radiation and what is referred to within this patent. Simple re-radiation is a re-transmission of all satellite signals in view at a single antenna.
Regardless, re-radiation is not a precise form of positioning. If you re-radiate signals, you are essentially inducing a type of multipath, which degrades accuracy. What the essence of this patent claims is that simple re-radiation system can be improved by using directional antennas that could be used to track specific satellites within a field of view, such as one antenna being responsible for tracking only a quadrant facing North. The benefit is that the a satellite in one direction could made available within the building from a similar direction as seen by the user, as opposed to being made available from the same location as all satellites. If there's a Northern satellite, there's no point in re-transmitting the signal from a single antenna on the South side of the building.This is an incremental improvement over using a one-antenna-based solution, however is still completely impractical and illogical, since it does not directly solve the problem. Not to mention that there are a host of technical challenges that defeat the value of this system.A proper method of indoor GPS positioning would be to have a number of psueduolites spread out and visible throughout the area of operation.
This is a completely independent setup of a GPS system. I'm sure that this could be accomplished affordably if commercially developed, but the FCC becomes an issue. And as Mike mentioned, there are likely commercially viable and affordable systems out there already that are using free or licensed spectrum, where there's no problem with protection and safety of navigation services.
Brendon
That looks like a diagram for GPS MIND CONTROL.
..."GPS Repeater" ok whatever.
This is not new. I installed a GPS repeater in the basement lab of my office building 2 years ago. These have been in use for years in the aviation and emergency services industry to improve acquisition times for firetrucks, police vehicles, and airplanes when leaving garages and hangars.
Generally you need a license from the FCC to operate one of these because it will mess with GPS equipment when you have leaking amlified and repeated GPS signals coming from a building.